Effects of Modification of Pain Protocol on Incidence of Post Operative Nausea and Vomiting

Background: A Perioperative Surgical Home (PSH) care model applies a standardized multidisciplinary approach to patient care using evidencebased medicine to modify and improve protocols. Analysis of patient outcome measures, such as postoperative nausea and vomiting (PONV), allows for refinement of existing protocols to improve patient care. We aim to compare the incidence of PONV in patients who underwent primary total joint arthroplasty before and after modification of our PSH pain protocol. Methods: All total joint replacement PSH (TJR-PSH) patients who underwent primary THA (n=149) or TKA (n=212) in the study period were included. The modified protocol added a single dose of intravenous (IV) ketorolac given in the operating room and oxycodone immediate release orally instead of IV Hydromorphone in the Post Anesthesia Care Unit (PACU). The outcomes were (1) incidence of PONV and (2) average pain score in the PACU. We also examined the effect of primary anesthetic (spinal vs. GA) on these outcomes. The groups were compared using chi-square tests of proportions. Results: The incidence of post-operative nausea in the PACU decreased significantly with the modified protocol (27.4% vs. 38.1%, p=0.0442). There was no difference in PONV based on choice of anesthetic or procedure. Average PACU pain scores did not differ significantly between the two protocols. Conclusion: Simple modifications to TJR-PSH multimodal pain management protocol, with decrease in IV narcotic use, resulted in a lower incidence of postoperative nausea, without compromising average PACU pain scores. This report demonstrates the need for continuous monitoring of PSH pathways and implementation of revisions as needed.